Improvement in mills for grinding quartz



Y 3 Sheets-Sheet 1.

s. CRAM.

Ore Mill.

Patented Feb. 10, 1852.

AM.PHOT0'LlTHO.C0-N.Y. (DSBDRNE'S PROCESS) 3 Sheets- -Sheet 2. S. CRAM.

Ore Mill.

Patented Feb. 10, 1852.

3 Sheets-Sheet 3. s. CRAM.

' Ore Mm. N0. 8,718. Patented Feb. 10, 1852,

AM. PHDTO-LITHCLCQNX. LOSBURNE'S PROCESS.)

UNITED STATES PATENT Fries.

SMITH CRAM, OF NEW YORK, N. Y.

IMPROVEMENT lN MILLS FOR GRINDING QUARTZ.

Specification forming part of Letters Patent No. 8,71%, dated February 10, 1852.

To aZZ whom it may concern:

Be it known that I, SMITH ORAM, of the city, county, and State of New York, have invented a new and useful Improved Machine for Crushing and Grinding Quartz, &c., of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, which form part of this specification, and in which Figure 1 represents a view in perspective of my quartz crusher and grinder. Fig. 2 is a plan thereof, and Fig. 3 is a transverse section of the same.

My quartz crusher and grinder consists, mainly, of a horizontal annular trough and of two vertical crushing wheels, which are caused to rotate in the trough and at the same time to revolve around a central axis.

In the accompanying drawings, A is the annular trough, which is formed of massive segments of cast-iron firmly secured to each other. The interior of the trough is divided into two concentric wedge-formed grindingchambers b b by an annular ridge 0, so that the general section of the interior of the trough resembles the letter W. The outer and inner rims of the trough are surmounted by diverging segments of wood (1 d, which prevent the overflowing of the substance being ground.

At the center of the annular trough is an upright standard E, whose upper extremity forms a pivot-journal f, on which a short upright shaft G is stepped. The upper extrernity or journal of this upright shaft is received in a hearing or pillow-block secured to a strong frame H, whose extremities are supported by posts I I, which are projected upward from the bed on which the machine is placed, and to which they are firmly secured. The lower extremity of the upright shaft is forked to embrace a horizontal axle J, which is pivoted loosely upon the pivot-journal of the central standard E, and whose arms is 70 extend in opposite directions over the trough beneath. Each arm of the horizontal axle-tree is fitted with a massive crushing-wheel M. The rims of these wheels are formed of segments of cast-iron firmly secured together by dovetailed keys. The peripheries of the rims are formed into angular grooves and ridges whose sectionscorrespond with those of the ridges and grooves of the trough in which the wheels are arranged to run, the two bearing the same relation to each other as a screw and its nut. The middle of each grinding-wheel is fitted with a tubular box a, which rotates upon the corresponding arm of the horizontal axle J, and the body of the wheel which is contained between the tubular box and the segmental rim is formed of a series of removable disks Z Z Z Z Z, which are secured to each other and to the tubular box and segmental rim by screw-bolts or other suitable connections. Each wheel is prevented from working off the axle-arm by a washer and linchpin.

The upright shaft G has a large beveled wheel P secured to it, whose teeth engage with those of a corresponding beveled pinion R. The latter is secured to a horizontal shaft S, to which a rotary motion is imparted by a steanrengine or other prime mover of the requisite force. The crusher and grinder represented in the drawings is arranged to be driven by a reciprocating steam-engine whose crank T is secured to the pinion-shaft.

NVhen the pinion-shaft is put in motion, it turns the cog-Wheel P and the upright shaft to which it is secured. The latter moves the axle and thus forces the crushing and grinding-wheels to roll around in the trough. In this movement the faces ofthe angular ridges of the wheel-rims grind upon the corresponding faces of the angular grooves of the bed, while as the axle on which they turn is pivoted loosely upon the central standard the wheels are free to rise, roll upon and crush by their weight and movement the substances lying in their track in the trough. This compound crushing and grinding movement is greatly enhanced by the form of the wheelrims and trough, which is not a matter of indifference, for if they be not properly formed a machine of such ponderous weight and size will only work imperfectly, if at all. In order, therefore, to insure perfect action and to give the wheels a tendency to run in the center of the grooves, the inner sides of the grooves of the trough and the corresponding sides of the ridges of the wheel-rims should have the forms of frusta of cones whose apexes meet at the intersection of the vertical axis of the trough with the horizontal axes of the wheels, as shown by the red lines in Fig. 3, while the outer sides of the grooves of the trough and the corresponding sides of the ridges of the wheels should have the form of zones of spheres whose centers are at the point of intersection of the axes of the trough and wheels, as also shown in red lines in Fig. 3. The surfaces of the wheel-rims will then apply themselves truly to those of the trough and will insure the best grinding action.

Each wheel in rolling grasps the lumps of the quartz or other substance being ground in the groove between its two ridges, and thus preventing their escape sidewise crushes them upon the ridge of the trough. The crushing action of the apparatus is insured by the great weight of the wheels, which in the machine I have built weigh twenty-five tons apiece, while the grinding action of the machine is rendered equallysure by the compound rolling and rubbing movement of the surfaces of the wheels and trough upon each other, and these surfaces should be chilled in casting to insure hardness and durability.

The method I have described of constructing the crushing-wheels and trough of sections is of great importance to the practical value of the machine. In the first place it enables me to form the machine of a series of pieces of a convenient size to be readily removed from place to place and to be transported over mountainous regions, such as exist in California, where it would be impracticable to convey masses of the weight and size of the wheels or trough if made in one piece. In the second place it permits of the replacement of the rims, when worn, at asmall cost compared with that of an entire new crushing-wheel; but another and most important advantage of this method of construction is that it permits of the graduation of the weight of the crushing-Wheels to the quality of the substance upon which they are to act. Thus, for example, refractory quartz may require the full weight of all the sections of each crushing-Wheel, while softer qualities may be crushed with equal efficiency and much less power by wheels of lighter weight, and in this case one or more of the disks which form the bodies of the wheels may be removed to lighten their weight as may be found expedient. Whenever disks are thus removed, washers of the same thickness should be slipped over the connecting-bolts to keep the remaining disks in their proper places, and the wheel must be again clamped up.

The substances to be ground by this machine should first be broken into coarse fragments either by hand-hammers or by a stamping-mill. After they have been ground to a sufficient fineness in the mill they may either be removed therefrom by means of scoops, or a portion of the trough may be made removable to form a spout through which the fine quartz may be washed by means of a stream of water.

In putting up the machine herein described I contemplate using the circular basin contained within the annular trough as an arrastra to triturate the ground quartz with quicksilver. To adapt the machine to this purpose, the interior of the circular basin is paved with granite or with some other hard substance to form the bed of the arrastra, and the moving stones should be connected by chains with arms projected from the upright shaft which drives the axle of the grinding-wheels; or, if preferred, these stones may be connected by their chains with the arms of the axle-tree. \Vhen the machine is arranged in this manner, the ground quartz from the mill may be discharged through a spout, as above described, directly into the central basin, and after the powder has been sufficiently ground by the action of the arrastra it may be discharged through a pipe passing beneath the annular trough of the mill and conducted to any suitable apparatus, to be subjected to washing or any other process, as may be deemed expedient.

VVhatI claim as my invention, and desire to secure by Letters Patent, is

, l. The crushing and grinding mill herein described, consisting of a trough and one or more rotating wheels, the acting surfaces of both the wheels and trough being formed as herein set forth, so that the former will run in the latter without tendency to run over its edges, except as it maybe influenced by centrifugal force.

2. The combination of a double-ridged wheel-rim with a trough of corresponding form, whereby the lumps of quartz or other substance being ground are grasped by the wheel in its rolling between the angular groove or furrow contained between the two ridges and, being thus prevented from escaping laterally are, crushed upon the ridge of the trough with much less force and greater effect than if the angular action of the ridges were counteracted by the embedding of the lumps to be crushed among smaller granular and pulverized particles, which is always the case when the concave or inner angle is below and the convex or outer angle above, which is the converse of the combination to which this claim refers.

3. The method of constructing the wheels of a crushing and grinding mill of removable sections, substantially in the manner and for the purpose herein set forth.

In testimony whereof I have hereunto subscribed my name.

SMITH ORAM.

Witnesses:

P. H. WATsoN, E. S. RENwIoK. 

